Percentages

Question 1

What are the formulas for when you are increasing or decreasing a value and its most common variations?

Answer 1

Increase

New Value = Old Value * (1 + %/100)

Old Value = New Value/ (1 + %/100)

Decrease:

New Value = Old Value * (1 - %/100)

Old Value = New Value/ (1 - %/100)

Question 2

What are the formulas for percentage change?

Answer 2

There are two standard formulas:

1.- Change in Percentage

Change in Percentage = (Final Value - Initial Value / Initial Value) * 100

2.- Change in percentage compounded

((Final Value / Initial Value) - 1) * 100

Question 3

What are the formulas for Original Price (past price) with a fixed and variable amount?

Answer 3

Increase:

Original price = F/P2-P1

Decrease:

Original Price = P1- P2

F = Fixed Amount
P1 = Initial percentage
P2 = Final Percentage

Question 4

What is the formula for gain or loss when dealing with shares?

Answer 4

1.- Formula for value method

Net Gain/Loss = ((Batch 1 - Total Sale/1+profit %/100) + (Batch 2 - Total Sale/1-loss %/100)) - Total Sale (Batch 1 + 2)

2.- Net Gain/Loss = (( Share price - sale share price/1+profit %/100) * # of shares) + (( Share price - sale share price/1-loss %/100) * # of shares)

3.- Average share price:

Portafolio Value/number of shares = average share price0.

Question 5

What are 4 important notes for percentages?

Answer 5

1.- “OF” means multiplication, and you’re not adding value to the original amount.

Example.

X is 200% of Y:

X=2Y

*If it said something like greater or increased by, then it would be x=3Y

2.- “More than” ( and its variations) implies an increase:

Example:

X is 200% more than Y:

X=3Y

3.- When a problem states: “X is Y percentage of Z”

X = Y/100 * X

4.- What percentage of Z is Y?

It’s asking you how much of Z is made up of Y

Y/Z * 100

*When asked what “what percentage of A is B?” Letter A will always be on the denominator:

Percentage = (B/A)*100

Question 6

Same increase Twice, no change in Price - what Does it mean?

Answer 6

If a value increases by the same amount from the first to the second period and then from the second to the third period, the overaal percetage change form the first to the third period is ZERO.

Example: If the profits of company X from Y1 to Y2 increased by the same amount as from Y2 to Y3, then the overral percentage change in profits from Y1-Y3 is 0%.